Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | #include <linux/kernel.h> |
| 3 | #include <linux/errno.h> |
| 4 | #include <linux/fs.h> |
| 5 | #include <linux/file.h> |
| 6 | #include <linux/fdtable.h> |
| 7 | #include <linux/fsnotify.h> |
| 8 | #include <linux/namei.h> |
| 9 | #include <linux/io_uring.h> |
| 10 | |
| 11 | #include <uapi/linux/io_uring.h> |
| 12 | |
| 13 | #include "../fs/internal.h" |
| 14 | |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 15 | #include "io_uring.h" |
Jens Axboe | 7357298 | 2022-06-13 07:12:45 -0600 | [diff] [blame] | 16 | #include "rsrc.h" |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 17 | #include "openclose.h" |
| 18 | |
| 19 | struct io_open { |
| 20 | struct file *file; |
| 21 | int dfd; |
| 22 | u32 file_slot; |
| 23 | struct filename *filename; |
| 24 | struct open_how how; |
| 25 | unsigned long nofile; |
| 26 | }; |
| 27 | |
| 28 | struct io_close { |
| 29 | struct file *file; |
| 30 | int fd; |
| 31 | u32 file_slot; |
| 32 | }; |
| 33 | |
Jens Axboe | dc18b89 | 2023-12-07 20:06:02 -0700 | [diff] [blame] | 34 | struct io_fixed_install { |
| 35 | struct file *file; |
| 36 | unsigned int o_flags; |
| 37 | }; |
| 38 | |
Dylan Yudaken | 0ffae64 | 2023-01-27 05:52:27 -0800 | [diff] [blame] | 39 | static bool io_openat_force_async(struct io_open *open) |
| 40 | { |
| 41 | /* |
| 42 | * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open, |
Aleksa Sarai | 72dbde0 | 2023-08-07 12:24:15 +1000 | [diff] [blame] | 43 | * it'll always -EAGAIN. Note that we test for __O_TMPFILE because |
| 44 | * O_TMPFILE includes O_DIRECTORY, which isn't a flag we need to force |
| 45 | * async for. |
Dylan Yudaken | 0ffae64 | 2023-01-27 05:52:27 -0800 | [diff] [blame] | 46 | */ |
Aleksa Sarai | 72dbde0 | 2023-08-07 12:24:15 +1000 | [diff] [blame] | 47 | return open->how.flags & (O_TRUNC | O_CREAT | __O_TMPFILE); |
Dylan Yudaken | 0ffae64 | 2023-01-27 05:52:27 -0800 | [diff] [blame] | 48 | } |
| 49 | |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 50 | static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
| 51 | { |
Stefan Metzmacher | f2ccb5a | 2022-08-11 09:11:15 +0200 | [diff] [blame] | 52 | struct io_open *open = io_kiocb_to_cmd(req, struct io_open); |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 53 | const char __user *fname; |
| 54 | int ret; |
| 55 | |
| 56 | if (unlikely(sqe->buf_index)) |
| 57 | return -EINVAL; |
| 58 | if (unlikely(req->flags & REQ_F_FIXED_FILE)) |
| 59 | return -EBADF; |
| 60 | |
| 61 | /* open.how should be already initialised */ |
| 62 | if (!(open->how.flags & O_PATH) && force_o_largefile()) |
| 63 | open->how.flags |= O_LARGEFILE; |
| 64 | |
| 65 | open->dfd = READ_ONCE(sqe->fd); |
| 66 | fname = u64_to_user_ptr(READ_ONCE(sqe->addr)); |
| 67 | open->filename = getname(fname); |
| 68 | if (IS_ERR(open->filename)) { |
| 69 | ret = PTR_ERR(open->filename); |
| 70 | open->filename = NULL; |
| 71 | return ret; |
| 72 | } |
| 73 | |
| 74 | open->file_slot = READ_ONCE(sqe->file_index); |
| 75 | if (open->file_slot && (open->how.flags & O_CLOEXEC)) |
| 76 | return -EINVAL; |
| 77 | |
| 78 | open->nofile = rlimit(RLIMIT_NOFILE); |
| 79 | req->flags |= REQ_F_NEED_CLEANUP; |
Dylan Yudaken | 0ffae64 | 2023-01-27 05:52:27 -0800 | [diff] [blame] | 80 | if (io_openat_force_async(open)) |
| 81 | req->flags |= REQ_F_FORCE_ASYNC; |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 82 | return 0; |
| 83 | } |
| 84 | |
| 85 | int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
| 86 | { |
Stefan Metzmacher | f2ccb5a | 2022-08-11 09:11:15 +0200 | [diff] [blame] | 87 | struct io_open *open = io_kiocb_to_cmd(req, struct io_open); |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 88 | u64 mode = READ_ONCE(sqe->len); |
| 89 | u64 flags = READ_ONCE(sqe->open_flags); |
| 90 | |
| 91 | open->how = build_open_how(flags, mode); |
| 92 | return __io_openat_prep(req, sqe); |
| 93 | } |
| 94 | |
| 95 | int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
| 96 | { |
Stefan Metzmacher | f2ccb5a | 2022-08-11 09:11:15 +0200 | [diff] [blame] | 97 | struct io_open *open = io_kiocb_to_cmd(req, struct io_open); |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 98 | struct open_how __user *how; |
| 99 | size_t len; |
| 100 | int ret; |
| 101 | |
| 102 | how = u64_to_user_ptr(READ_ONCE(sqe->addr2)); |
| 103 | len = READ_ONCE(sqe->len); |
| 104 | if (len < OPEN_HOW_SIZE_VER0) |
| 105 | return -EINVAL; |
| 106 | |
| 107 | ret = copy_struct_from_user(&open->how, sizeof(open->how), how, len); |
| 108 | if (ret) |
| 109 | return ret; |
| 110 | |
| 111 | return __io_openat_prep(req, sqe); |
| 112 | } |
| 113 | |
| 114 | int io_openat2(struct io_kiocb *req, unsigned int issue_flags) |
| 115 | { |
Stefan Metzmacher | f2ccb5a | 2022-08-11 09:11:15 +0200 | [diff] [blame] | 116 | struct io_open *open = io_kiocb_to_cmd(req, struct io_open); |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 117 | struct open_flags op; |
| 118 | struct file *file; |
| 119 | bool resolve_nonblock, nonblock_set; |
| 120 | bool fixed = !!open->file_slot; |
| 121 | int ret; |
| 122 | |
| 123 | ret = build_open_flags(&open->how, &op); |
| 124 | if (ret) |
| 125 | goto err; |
| 126 | nonblock_set = op.open_flag & O_NONBLOCK; |
| 127 | resolve_nonblock = open->how.resolve & RESOLVE_CACHED; |
| 128 | if (issue_flags & IO_URING_F_NONBLOCK) { |
Dylan Yudaken | 0ffae64 | 2023-01-27 05:52:27 -0800 | [diff] [blame] | 129 | WARN_ON_ONCE(io_openat_force_async(open)); |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 130 | op.lookup_flags |= LOOKUP_CACHED; |
| 131 | op.open_flag |= O_NONBLOCK; |
| 132 | } |
| 133 | |
| 134 | if (!fixed) { |
| 135 | ret = __get_unused_fd_flags(open->how.flags, open->nofile); |
| 136 | if (ret < 0) |
| 137 | goto err; |
| 138 | } |
| 139 | |
| 140 | file = do_filp_open(open->dfd, open->filename, &op); |
| 141 | if (IS_ERR(file)) { |
| 142 | /* |
| 143 | * We could hang on to this 'fd' on retrying, but seems like |
| 144 | * marginal gain for something that is now known to be a slower |
| 145 | * path. So just put it, and we'll get a new one when we retry. |
| 146 | */ |
| 147 | if (!fixed) |
| 148 | put_unused_fd(ret); |
| 149 | |
| 150 | ret = PTR_ERR(file); |
| 151 | /* only retry if RESOLVE_CACHED wasn't already set by application */ |
| 152 | if (ret == -EAGAIN && |
| 153 | (!resolve_nonblock && (issue_flags & IO_URING_F_NONBLOCK))) |
| 154 | return -EAGAIN; |
| 155 | goto err; |
| 156 | } |
| 157 | |
| 158 | if ((issue_flags & IO_URING_F_NONBLOCK) && !nonblock_set) |
| 159 | file->f_flags &= ~O_NONBLOCK; |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 160 | |
| 161 | if (!fixed) |
| 162 | fd_install(ret, file); |
| 163 | else |
| 164 | ret = io_fixed_fd_install(req, issue_flags, file, |
| 165 | open->file_slot); |
| 166 | err: |
| 167 | putname(open->filename); |
| 168 | req->flags &= ~REQ_F_NEED_CLEANUP; |
| 169 | if (ret < 0) |
| 170 | req_set_fail(req); |
| 171 | io_req_set_res(req, ret, 0); |
| 172 | return IOU_OK; |
| 173 | } |
| 174 | |
| 175 | int io_openat(struct io_kiocb *req, unsigned int issue_flags) |
| 176 | { |
| 177 | return io_openat2(req, issue_flags); |
| 178 | } |
| 179 | |
| 180 | void io_open_cleanup(struct io_kiocb *req) |
| 181 | { |
Stefan Metzmacher | f2ccb5a | 2022-08-11 09:11:15 +0200 | [diff] [blame] | 182 | struct io_open *open = io_kiocb_to_cmd(req, struct io_open); |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 183 | |
| 184 | if (open->filename) |
| 185 | putname(open->filename); |
| 186 | } |
| 187 | |
Jens Axboe | f110ed8 | 2022-06-13 04:42:56 -0600 | [diff] [blame] | 188 | int __io_close_fixed(struct io_ring_ctx *ctx, unsigned int issue_flags, |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 189 | unsigned int offset) |
| 190 | { |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 191 | int ret; |
| 192 | |
| 193 | io_ring_submit_lock(ctx, issue_flags); |
Jens Axboe | f110ed8 | 2022-06-13 04:42:56 -0600 | [diff] [blame] | 194 | ret = io_fixed_fd_remove(ctx, offset); |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 195 | io_ring_submit_unlock(ctx, issue_flags); |
Jens Axboe | f110ed8 | 2022-06-13 04:42:56 -0600 | [diff] [blame] | 196 | |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 197 | return ret; |
| 198 | } |
| 199 | |
| 200 | static inline int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags) |
| 201 | { |
Stefan Metzmacher | f2ccb5a | 2022-08-11 09:11:15 +0200 | [diff] [blame] | 202 | struct io_close *close = io_kiocb_to_cmd(req, struct io_close); |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 203 | |
Jens Axboe | f110ed8 | 2022-06-13 04:42:56 -0600 | [diff] [blame] | 204 | return __io_close_fixed(req->ctx, issue_flags, close->file_slot - 1); |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 205 | } |
| 206 | |
| 207 | int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
| 208 | { |
Stefan Metzmacher | f2ccb5a | 2022-08-11 09:11:15 +0200 | [diff] [blame] | 209 | struct io_close *close = io_kiocb_to_cmd(req, struct io_close); |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 210 | |
| 211 | if (sqe->off || sqe->addr || sqe->len || sqe->rw_flags || sqe->buf_index) |
| 212 | return -EINVAL; |
| 213 | if (req->flags & REQ_F_FIXED_FILE) |
| 214 | return -EBADF; |
| 215 | |
| 216 | close->fd = READ_ONCE(sqe->fd); |
| 217 | close->file_slot = READ_ONCE(sqe->file_index); |
| 218 | if (close->file_slot && close->fd) |
| 219 | return -EINVAL; |
| 220 | |
| 221 | return 0; |
| 222 | } |
| 223 | |
| 224 | int io_close(struct io_kiocb *req, unsigned int issue_flags) |
| 225 | { |
| 226 | struct files_struct *files = current->files; |
Stefan Metzmacher | f2ccb5a | 2022-08-11 09:11:15 +0200 | [diff] [blame] | 227 | struct io_close *close = io_kiocb_to_cmd(req, struct io_close); |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 228 | struct file *file; |
| 229 | int ret = -EBADF; |
| 230 | |
| 231 | if (close->file_slot) { |
| 232 | ret = io_close_fixed(req, issue_flags); |
| 233 | goto err; |
| 234 | } |
| 235 | |
| 236 | spin_lock(&files->file_lock); |
Christian Brauner | 50d910d | 2023-10-10 10:23:26 +0200 | [diff] [blame] | 237 | file = files_lookup_fd_locked(files, close->fd); |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 238 | if (!file || io_is_uring_fops(file)) { |
| 239 | spin_unlock(&files->file_lock); |
| 240 | goto err; |
| 241 | } |
| 242 | |
| 243 | /* if the file has a flush method, be safe and punt to async */ |
| 244 | if (file->f_op->flush && (issue_flags & IO_URING_F_NONBLOCK)) { |
| 245 | spin_unlock(&files->file_lock); |
| 246 | return -EAGAIN; |
| 247 | } |
| 248 | |
Christian Brauner | 24fa3ae | 2023-11-30 13:49:08 +0100 | [diff] [blame] | 249 | file = file_close_fd_locked(files, close->fd); |
Jens Axboe | cd40cae | 2022-05-24 21:54:43 -0600 | [diff] [blame] | 250 | spin_unlock(&files->file_lock); |
| 251 | if (!file) |
| 252 | goto err; |
| 253 | |
| 254 | /* No ->flush() or already async, safely close from here */ |
| 255 | ret = filp_close(file, current->files); |
| 256 | err: |
| 257 | if (ret < 0) |
| 258 | req_set_fail(req); |
| 259 | io_req_set_res(req, ret, 0); |
| 260 | return IOU_OK; |
| 261 | } |
Jens Axboe | dc18b89 | 2023-12-07 20:06:02 -0700 | [diff] [blame] | 262 | |
| 263 | int io_install_fixed_fd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
| 264 | { |
| 265 | struct io_fixed_install *ifi; |
| 266 | unsigned int flags; |
| 267 | |
| 268 | if (sqe->off || sqe->addr || sqe->len || sqe->buf_index || |
| 269 | sqe->splice_fd_in || sqe->addr3) |
| 270 | return -EINVAL; |
| 271 | |
| 272 | /* must be a fixed file */ |
| 273 | if (!(req->flags & REQ_F_FIXED_FILE)) |
| 274 | return -EBADF; |
| 275 | |
| 276 | flags = READ_ONCE(sqe->install_fd_flags); |
| 277 | if (flags & ~IORING_FIXED_FD_NO_CLOEXEC) |
| 278 | return -EINVAL; |
| 279 | |
Paul Moore | 16bae3e | 2024-01-23 16:55:02 -0500 | [diff] [blame] | 280 | /* ensure the task's creds are used when installing/receiving fds */ |
| 281 | if (req->flags & REQ_F_CREDS) |
| 282 | return -EPERM; |
| 283 | |
Jens Axboe | dc18b89 | 2023-12-07 20:06:02 -0700 | [diff] [blame] | 284 | /* default to O_CLOEXEC, disable if IORING_FIXED_FD_NO_CLOEXEC is set */ |
| 285 | ifi = io_kiocb_to_cmd(req, struct io_fixed_install); |
| 286 | ifi->o_flags = O_CLOEXEC; |
| 287 | if (flags & IORING_FIXED_FD_NO_CLOEXEC) |
| 288 | ifi->o_flags = 0; |
| 289 | |
| 290 | return 0; |
| 291 | } |
| 292 | |
| 293 | int io_install_fixed_fd(struct io_kiocb *req, unsigned int issue_flags) |
| 294 | { |
| 295 | struct io_fixed_install *ifi; |
| 296 | int ret; |
| 297 | |
| 298 | ifi = io_kiocb_to_cmd(req, struct io_fixed_install); |
| 299 | ret = receive_fd(req->file, NULL, ifi->o_flags); |
| 300 | if (ret < 0) |
| 301 | req_set_fail(req); |
| 302 | io_req_set_res(req, ret, 0); |
| 303 | return IOU_OK; |
| 304 | } |